Biology subjects

Holly, R. W.

Publications and source records attributed to Holly, R. W..

3 recordsLinked to original sources

bioRxiv2025

Targeted Nanoparticles: an Innovative Modality in the Treatment of Cancer

Despite progress made in the development of anticancer therapeutics, traditional small-molecule chemotherapeutics often struggle to overcome toxicity, efficacy, and off-target effects. These specific issues can be overcome by either encapsulating the drug or by targeting it directly to the tumor cell. Here, we describe a novel targeted nanoparticle (referred to as a nano-antibody-drug conjugate Targeted Nanosphere or nADC/TNS), based cancer therapeutic platform that can improve the efficacy of a broad range of existing therapeutics. Targeting is antibody-directed, as with antibody-drug conjugates (ADCs). Still, the payload per antibody is vastly greater by orders of magnitude (a thousand for nADC/TNS versus two to eight for ADCs). The nADC/TNS consists of an approximately 80 nm drug-filled nanoparticle composed of phospholipids, cholesterol, and UV cross-linkable diacetylene lipids. We describe the preparation, characterization, and evaluation of nADC/TNS as a novel, versatile, and effective treatment modality for cancer and potentially other diseases. This report focuses on data with nADC/TNS variants NV101 (anti-CD99 targeted, doxorubicin-filled), NV102 (anti-CD19 targeted, doxorubicin-filled), and NV103 (anti-CD99 targeted, irinotecan-filled). We investigated NV101 and NV103 in a mouse model with implanted and metastatic Ewing tumors (ES). NV101 demonstrated significant tumor burden reduction while NV103 induced complete ablation of ES tumors. NV102 demonstrated complete ablation of chemotherapy-resistant relapsed adult lymphocytic leukemia (ALL). These results document the potential superior efficacy of antibody-targeted nanoparticles containing a variety of small-molecule payloads, compared to their free molecule equivalents.

biochemistry↗

bioRxiv2025

Catalytic degradation of circulating targets with FcRn-mediated cycling LYTACs

Circulating proteins are common targets for the discovery of occupancy-based inhibitors including monoclonal antibodies. Effective inhibition of target pathogenicity with blocking approaches, however, is often challenged by target parameters that lead to insufficient occupancy and/or incomplete pharmacology limited by only single site binding. Extracellular targeted protein degradation approaches, such as lysosomal targeting chimeras (LYTACs), offer an opportunity to minimize these challenges by an event-driven mechanism that selectively, thoroughly and irreversibly eliminates drivers of disease. First generation LYTACs, designed to traffic to the lysosome, show limited durability since the therapeutic is degraded along with the target protein of interest. Here we describe cataLYTACs, which overcome this limitation by combining stabilized asialoglycoprotein (ASGPR) ligands, pH-sensitive target binding and recycling via the neonatal Fc receptor (FcRn). These cataLYTACs degraded superstoichiometric levels of a target protein, IgE, in vitro and demonstrated deep and sustained clearance of human IgE in mouse models. In non-human primates, cataLYTACs resulted in >98% clearance of circulating endogenous IgE for 2 weeks and outperformed the standard of care blocking antibody, omalizumab (Xolair(R)), in both free IgE elimination and duration of action. CataLYTACs represent a new therapeutic modality for a wide range of disease states driven by circulating factors, with the potential for superior efficacy and duration of action compared to traditional inhibitors.

cell biology↗

bioRxiv2024

Monitoring lysosomal catabolism: a sensitive probe for assessing targeted lysosomal degradation of extracellular proteins

Extracellular targeted protein degradation (eTPD) is an emerging therapeutic field. The Lysosome targeting chimera (LYTAC) is a therapeutic modality that promotes degradation of extracellular drivers of disease in the lysosome. While widely available pH-sensitive probes may report on lysosome delivery, these probes do not necessarily report on the enzymatically active functional state of the lysosome. We report the development and application of a sensitive fluorescent probe, LysoLight Deep Red, to monitor catabolism of internalized proteins in the lysosome based on cleavage by cathepsin proteases. We demonstrate the application of Lysolight Deep Red to monitor the catabolic fate of therapeutic monoclonal antibodies, ASGPR-targeted LYTAC therapeutics and LYTAC targets in immortalized cell lines and in primary human hepatocytes.

cell biology↗